Most people, when listening to recorded music, will occasionally glance at the sound source as a particular sound or combination of sound reaches their consciousness, as if in need of an explanation or a further stimulation at that particular time. The conventional sound-transmitting speaker is of course incapable of providing that further stimulation, but it is almost as if the listener half-expects that by looking at the source of the sound he could thereby appreciate it better. There will always be purists who choose to listen to music visually unaided, with their eyes closed, and perhaps create their own abstract images within their own mind either consciously or subconsciously. Despite this, however, there must be a market for an apparatus capable of translating recorded or live music into a range of observable movements.
Electronic systems for analysing recorded sound and translating the results into observable form are already known. These are typified by the modern flashing-light units used in discotheques and now used by an increasing number of performers as part of their on-stage equipment. The electronic circuitry for such systems is, however, not usually designed to drive an inductive load such as a variable-speed electric motor, and the visual effects produced by these systems contain no moving element.